Pushbutton construction for pushbutton-type tuning apparatus



Dec. 8, 1970 TAMAKl QHASHI PUSHBUTTONbONSTRUCTION FOR PUSHBUTTON-TYPE TUNING APPARATUS 'Filed Nov. 26. 1968 s AFT- IINVEN'IIOR.

BY *6 g;

ATTORNEY United States Patent 01 :"fice 3,545,289 Patented Dec. 8, 1970 3,545,289 PUSHBUTTON CONSTRUCTION FOR PUSH- BUTTON-TYPE TUNING APPARATUS Tamaki Ohashi, 2-chome, Tanashi-shi, Tokyo, Japan Filed Nov. 26, 1968, Ser. No. 779,100 Int. Cl. F16h 35/18 US. Cl. 74-1033 7 Claims ABSTRACT OF THE DISCLOSURE DRAWING FIG. 1 is a top plan view, partly in section, of a push button construction, according to this invention, mounted on a machine frame;

FIG. 2 is a side view of the same;

FIG. 3 is a sectional view taken along line lII--III in FIG. 1; and

FIG. 4 is a top plan view, partly in section, of the pushbutton apparatus of FIG. 1 under set condition.

DETAILED DESCRIPTION This invention relates to an improved construction for a pushbutton-type tuning apparatus as used in a radio receiver or the like.

One kind of pushbutton apparatus hitherto known is of the type wherein an arm is provided with a setting plate for setting a tuning frequency, therebeing a locking member for locking the setting plate with a lever action and an actuating member for giving the lever action to the locking member. The actuating member is attached to a pushbutton member slidable mounted on the arm. This pushbutton apparatus is slidably mounted at right angles to cranks on a machine frame, therebeing a rotatable crank movable with a variable tuning element. The arrangement is such that, after the setting plate comes into contact with parallel rods associated with the crank due to a pushing of the pushbutton, the pushbutton can be further pushed to advance the actuating member in relation to the arm, whereupon the locking member is given the lever action for locking the setting plate in relation to the arm.

This kind of tuning system is so sharp in its selecting function that, for instance, in the case of a variable inductance element including a coil and core, an error in the order of mm. in the advancing and retracting position of the magnetic core relative to the coil body is not permissible. However, there is some play, which is unavoidable with usual manufacturing techniques, between the arm and the machine frame supporting the same. Due to the vertical direction of this play between the arm and the machine frame, if the direction of the pushbutton pushing force is varied the arm may advance with an upward or downward displacement. For this reason, even if the rotating angle of the crank is memorized accurately by the setting plate, the angle memorized by the setting plate cannot be reconstituted correctly on the crank and this will cause an error in the setting of the tuning frequency.

For obviating this defect, the Applicant has previously proposed a type of pushbutton apparatus wherein a first arm having a setting plate and a second arm having a pushbutton are provided. A pin on an actuating member projects through a guide groove in the first arm and is engaged with an inclined groove in the second arm. In this pushbutton apparatus, the two arms are mounted on a machine frame so as to be independently slidable. When the setting plate comes into contact with the parallel rods of the crank due to a pushing of the pushbutton, the pin is pushed by virtue of the inclined groove in an oblique direction so that an upward or downward force is exerted on the pin, whereby the pin pushes the first arm upwardly or downwardly through the guide groove. Thereby any play in vertical direction between the machine frame and the first arm can be substantially eliminated.

This action is similarly effected. in the case wherein, after the setting plate memorizes the rotating angle of the crank, the rotating angle is reconstituted on the crank, so that regardless of the direction of the pushbutton displacement force the angle between the crank and the setting plate can be accurately regulated. According to this construction, however, in order to give the first arm an upward or downward pushing force, it is required that the pin slide on the inclined surface of the inclined groove in accordance with the degree of the vertical directional play between the machine frame and the arm. However, the inclined surface of the inclined groove can be somewhat rough and the pin need not slide smoothly on the inclined surface. If the pin does not slide at all, the pin and the second arm are eifectively fixed together. Accordingly, a force component results for pushing the first arm in upper or lower direction which will not be exerted on the pin. If the inclination of the inclined groove is made larger in order to facilitate the sliding movement of the pin, the force component becomes unnecessarily large and the first arm strongly bites into the mounting portion of the machine frame and the automatic return of the pushbutton apparatus after release of the pushing force is affected.

An object of this invention is to obviate these defects and an embodiment of the invention will next be explained with reference to the accompanying drawing.

Element 1 is a first arm which is provided with a setting plate 3 rotatably supported thereon by means of a pin 2. A locking member 5 is swingably attached to a pin 4 mounted on a channel portion 1' formed on the arm 1 for locking the setting plate 3 with a lever action. An actuating member 6 is slidable within the channel portion 1' for giving the lever action to the locking member 5. The actuating member 6 has at its bottom surface a pin 7 which projects through a guide groove 8 extending longitudinally through the first arm. 1.

Element 9 is a second arm which has at its rear end a pushbutton 10. Element 11 is an intermediate member rotatably supported at one end on the pin 7. It is interposed between the two arms 1 and 9. The other end thereof is rotatably supported by a pin 12 on the second arm 9 in such a manner that the intermediate member 11 is inclined at an angle a in relation to the sliding movement or direction of the first arm 1.

The first arm 1 and the second arm 9 are mounted on the frame so as to be independently slidable aside from the connection to be later described. The rear portions of the arms 1 and 9 are in engagement with grooves 13 and 14 in the front frame plate A The front portions thereof are slidably supported on respective supporting rods 15 and 16 projecting from the rear frame plate A Element 17 is a return coil spring interposed between the rear frame plate A and the first arm 1. Element 18 is a stop provided on the first arm 1.

If the pushbutton 10 is pushed in the direction of an arrow a from the condition of FIG. 1, the arms 1 and 9 are both advanced and the setting plate 9 comes into contact with parallel rods b of a crank (not shown). If the pushbutton 10 is pushed further and strongly, the

second arm 9 and the actuating member 6 are advanced in relation to the first arm 1. The actuating member 6 then actuates the locking member for imparting to the same a lever action, and the locking member 5 then locks the setting plate 3, whereby the rotational angle of the crank (whose position has previously been determined by a manual tuning of the radio, etc.) is memorized by the plate 3. If, then, the pushbutton pushing force is released, the arms 1 and 9 are returned by the action of the coil spring 17 to the condition of FIG. 4. In the above progression, wherein the setting plate 3 comes in collision with the parallel rods 12 connected to the crank and is then locked, because of the inclination. of the intermediate member 11 in relation to the slide movement direction of the first arm 1, the pushbutton pushing force gives to the pin 12 a rotating force in counter-clockwise direction about the pin 7 and, at the same time, to the pin 7 a rotating force in counter-clockwise direction about the pin 12.

As a result, by the action of these rotating forces, the second arm 9 is forcibly pushed upwards and the first arm 1 is forcibly pushed downwards. These pushing forces are positively produced as long as the pushbutton 10 is being pushed. This action is similarly carried out when the setting plate 3 reproduces its memory rotating angle on the crank in response to a subsequent pushing of the pushbutton 10. Accordingly, play in vertical direction be tween the machine frame and the first arm can be substantially eliminated so that there results a pushbutton apparatus of high precision.

Additionally, the defect is cured which is due to the roughness of the surface of the inclined groove by reasons of which a force for pushing the first arm upwards or downwards can not be produced in the previously known pushbutton apparatus wherein a projecting member provided on the actuating member is mounted in an inclined groove in a second arm.

Additionally, since the operation can be assured, there is no necessity to produce too great a force for pushing the first arm upwards or downwards. Thus, the inclination angle of the intermediate member can be small. Accordingly, there is no fear that the arm might bite into the supporting portion of the machine frame, and the automatic return of the pushbutton apparatus becomes smooth.

According to this invention, additionally, the channel portion is formed on the first arm and that portion is mounted in the machine frame front plate, so that the mounting area between the first arm and the machine frame front plate is enlarged, whereby not only the slide movement of the first arm becomes smooth but also the biting-in phenomenon is reduced and is decreased for long use.

What is claimed is:

1. Pushbutton apparatus comprising first and second slidable arms, tuning selecting means on said first arm, a pushbutton on said second arm to displace the latter, and intermediate means between said arms so that movement of the second arm is transferred to the first arm and so that the second arm is subjected to a force translatory to the direction of movement of the second arm, said arms being parallel and said intermediate means compris ing a link pivotally connected to each of said arms.

2. Pushbutton apparatus as claimed in claim 1 wherein said link is normally inclined to the direction of move ment of the arms.

3. Pushbutton apparatus as claimed in claim 2 wherein said first arm includes a channel portion comprising locking means at least in part in the channel portion for setting and locking the tuning selecting means.

4. Pushbutton apparatus as claimed in claim 2, comprising pins connecting said link to said arms, said first arm being provided with a slot in which the corresponding pin is slidable.

5. Pushbutton apparatus as claimed in claim 4 wherein the selecting means is a segment which is pivotable on said first arm and said locking means includes a pivotal leverlike means to wedge the segment in fixed position and actuating means to lock the lever-like means into position.

6. Pushbutton apparatus as claimed in claim 5 comprising a frame supporting said arms and rods on said frame to guide said arms.

'7. Pushbutton apparatus as claimed in claim 5 wherein said corresponding pin is connected to the actuating means.

References Cited UNITED STATES PATENTS 2,928,283 3/1960 Teaf 74-1033 3,403,564 10/1968 Ohashi 7410.33

MILTON KAUFMAN, Primary Examiner US. Cl. X.R. 

